The Census 2020 redistricting data will be delivered to states by March 2021.
Preparations for use of these data and development of Census 2020-based plans should be underway by March 2020.
Existing 2010-based plans should be in redistricting packages by late 2020.

This section focuses on use of tools and data for redistricting a state by congressional districts
(CDs) and
a state by state legislative districts
(SLDs)
using decennial census geographic and demographic data.

Using GIS & GeoDemographics

Whether you are a
GIS
user or not yet using GIS, you can benefit from our self-paced, online course
Using GIS & GeoDemographics.
Learn more about using wide-ranging geography and subject matter to perform redistricting operations.
Evaluate existing plans. Learn about Census 2020 redistricting data file structures; access and use prototype data.
Analyze characteristics of voters and voting patterns.
Examine most recent voting precincts and related data.
View how census block and city demographics related to congressional districts and state legislative districts in your state(s) of interest.
See additional information.

Today one person can do what perhaps a team of 10 people would be required
to do for a similar redistricting application following the 2010 census.
Possibly more significant is the ability to convey alternative plans
to a wider set of stakeholders,
more easily and less expensively, through the Internet -- a capability which
has grown almost infinitely.

The Constitutionally mandated reason for the decennial census is for
Congressional reapportionment and the closely associated redistricting
process. Decennial census geographic and demographic data resources for use
in reapportionment and redistricting are described in a separate document.

Decennial census data are widely used
in other types of districting applications.
Local and state governments must redraw
boundaries to reflect changes in population size and composition.
Redistricting applications
include redistricting state legislatures, other types of
statewide geographic area redistrictings,
regional management areas,
sales territories,
school districts (attendance areas and election areas),
fire districts,
police beats,
city election districts, and other types of geography.

Role of GIS
Advancements in Geographic Information Systems (GIS)
offer new, faster, less expensive, and [potentially] more accurate
means of completing a successful redistricting operation.
Advancements in Internet-related technologies make it inexpensively
and readily achievable to make the results of multiple proposed plans
available for viewing with a Web browser. As a result, more stakeholders
have a better opportunity to review the scope of proposed
alternative plans. Finally, the results of the plans remain something of a
living resource--the GIS can be restarted at any time, if the components
are all retained and documented, and revisions can be made without starting
over with paper-sourced materials.

Review and monitor our unique resources
to learn about existing geographic and demographic data developments and
keep up-to-date on relevant new data resources and application issues.
For example, here you can learn about new Census 2010/2020 census block level
data from P.L. 94-171 and Summary File 1, what level of subject detail is available.
how to access the data, and find related sources of reference and data
user information.

Attend the Data Analytics Web Sessions learn
how to use software and data resources. If necessary, consider
a custom session focused on your redistricting needs to meet your
specific needs.

Download Census 2010/2020 geographic and demographic data resources
that can be "plugged directly into" the redistricting processes. For
example, you can
download Census 2000 county by census block
map files (and many other popular geographic layers) in shapefile format for your free unlimited use.

Use the
tools to convert no-cost downloaded ASCII
Census 2010/2020 data from the Census Bureau web server into database structure.

Use the data integration tools to automatically integrate the
Census 2010/2020 demographic data into map files in shapefile format.

Explore web-accessible interactive maps with
alternative plans made available on the Web. This type
of facility enables any stakeholder with a web browser to
access and compare alternative plans.

Contact ProximityOne for assistance with the collective process
of redistricting. We can help develop
basic specialized geographic concordance data files needed for the
redistricting process, assist in setting redistricting determinant factors
and acceptable deviations between districts, and even
and provide all provide the integrated set of
redistricting data files and software, prepare a base plan,
support the collective process of developing alternative plans, and
facilitate or directly implement web-based browser access to redistricting plans
through use of Internet tools, open architecture, mapserver operation.

Map boundary files that contain the small area geographic unit
building block geography for the area to be redistricted.

A cross-reference file that associates each of the unit building
blocks in the map files to an initial district within the area
to be redistricted (a file version of a base/starting point plan).

The demographic data that will be used as the basis for redrawing
the districts in the properly structured file covered the area to be
redistricted.

An understanding of the demographic subject matter factors and
how acceptable deviations from district to district will be defined/applied.

CV XE GIS software.

ProximityOne support services or staff who can develop, integrate, and operate these components.

Successful Redistricting Solutions
The key to successful use of any set of software and data software to develop
district plans
extension involves 1) understanding how to establish the base
data that convey the "starting point" for the plan
and 2) how to define parameters and deviations acceptable in the
redistricting process, and 3) acquiring and making the data components
available in the required formats and locations.

GIS software can then help create a plan and
alternative plans. The mapping software helps you create
and view a plan, manipulate and assign district elements (e.g. census
blocks), and dynamically recalculate statistical measures
for the districts.

Support Using these Resources
Learn more about demographic economic data and related analytical tools.
Join us in a Data Analytics Lab session.
Each informal session is focused on a specific topic.
The open structure also provides for Q&A and discussion of application issues of interest to participants.

ProximityOne User Group
Join the ProximityOne User Group
to keep up-to-date with new developments relating to geographic-demographic-economic decision-making information resources.
Receive updates and access to tools and resources available only to members.
Use this form to join the User Group.

Additional Information
ProximityOne develops geographic-demographic-economic data and analytical tools and helps organizations knit together and use diverse data in a decision-making and analytical framework. We develop custom demographic/economic estimates and projections, develop geographic and geocoded address files, and assist with impact and geospatial analyses.
Wide-ranging organizations use our software, data and methodologies to analyze their own data integrated with other data.
Follow ProximityOne on Twitter at
www.twitter.com/proximityone.
Contact ProximityOne (888-364-7656) with questions about data covered in this section or to discuss custom estimates, projections or analyses for your areas of interest.